Re: [PATCH 7/9] vfio/fsl-mc: Add irq infrastructure for fsl-mc devices

[Laurentiu Tudor <laurentiu.tudor@nxp.com>]

On 3/23/2020 7:19 PM, Diana Craciun wrote:
> This patch adds the skeleton for interrupt support
> for fsl-mc devices. The interrupts are not yet functional,
> the functionality will be added by subsequent patches.
> 
> Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
> Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
> ---
>  drivers/vfio/fsl-mc/Makefile              |  6 +-
>  drivers/vfio/fsl-mc/vfio_fsl_mc.c         | 71 ++++++++++++++++++++++-
>  drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c    | 63 ++++++++++++++++++++
>  drivers/vfio/fsl-mc/vfio_fsl_mc_private.h |  5 ++
>  4 files changed, 141 insertions(+), 4 deletions(-)
>  create mode 100644 drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
> 
> diff --git a/drivers/vfio/fsl-mc/Makefile b/drivers/vfio/fsl-mc/Makefile
> index 6f2b80645d5b..cad6dbf0b735 100644
> --- a/drivers/vfio/fsl-mc/Makefile
> +++ b/drivers/vfio/fsl-mc/Makefile
> @@ -1,2 +1,4 @@
> -vfio-fsl_mc-y := vfio_fsl_mc.o
> -obj-$(CONFIG_VFIO_FSL_MC) += vfio_fsl_mc.o
> +# SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)

nit: maybe the license should go in the first patch where the Makefile
gets created?

---
Best Regards, Laurentiu

> +
> +vfio-fsl-mc-y := vfio_fsl_mc.o vfio_fsl_mc_intr.o
> +obj-$(CONFIG_VFIO_FSL_MC) += vfio-fsl-mc.o
> diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> index ea5e81e7791c..4d7baee2e474 100644
> --- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> @@ -210,11 +210,75 @@ static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd,
>  	}
>  	case VFIO_DEVICE_GET_IRQ_INFO:
>  	{
> -		return -EINVAL;
> +		struct vfio_irq_info info;
> +
> +		minsz = offsetofend(struct vfio_irq_info, count);
> +		if (copy_from_user(&info, (void __user *)arg, minsz))
> +			return -EFAULT;
> +
> +		if (info.argsz < minsz)
> +			return -EINVAL;
> +
> +		if (info.index >= mc_dev->obj_desc.irq_count)
> +			return -EINVAL;
> +
> +		info.flags = VFIO_IRQ_INFO_EVENTFD;
> +		info.count = 1;
> +
> +		return copy_to_user((void __user *)arg, &info, minsz);
>  	}
>  	case VFIO_DEVICE_SET_IRQS:
>  	{
> -		return -EINVAL;
> +		struct vfio_irq_set hdr;
> +		u8 *data = NULL;
> +		int ret = 0;
> +
> +		minsz = offsetofend(struct vfio_irq_set, count);
> +
> +		if (copy_from_user(&hdr, (void __user *)arg, minsz))
> +			return -EFAULT;
> +
> +		if (hdr.argsz < minsz)
> +			return -EINVAL;
> +
> +		if (hdr.index >= mc_dev->obj_desc.irq_count)
> +			return -EINVAL;
> +
> +		if (hdr.start != 0 || hdr.count > 1)
> +			return -EINVAL;
> +
> +		if (hdr.count == 0 &&
> +		    (!(hdr.flags & VFIO_IRQ_SET_DATA_NONE) ||
> +		    !(hdr.flags & VFIO_IRQ_SET_ACTION_TRIGGER)))
> +			return -EINVAL;
> +
> +		if (hdr.flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK |
> +				  VFIO_IRQ_SET_ACTION_TYPE_MASK))
> +			return -EINVAL;
> +
> +		if (!(hdr.flags & VFIO_IRQ_SET_DATA_NONE)) {
> +			size_t size;
> +
> +			if (hdr.flags & VFIO_IRQ_SET_DATA_BOOL)
> +				size = sizeof(uint8_t);
> +			else if (hdr.flags & VFIO_IRQ_SET_DATA_EVENTFD)
> +				size = sizeof(int32_t);
> +			else
> +				return -EINVAL;
> +
> +			if (hdr.argsz - minsz < hdr.count * size)
> +				return -EINVAL;
> +
> +			data = memdup_user((void __user *)(arg + minsz),
> +					   hdr.count * size);
> +			if (IS_ERR(data))
> +				return PTR_ERR(data);
> +		}
> +
> +		ret = vfio_fsl_mc_set_irqs_ioctl(vdev, hdr.flags,
> +						 hdr.index, hdr.start,
> +						 hdr.count, data);
> +		return ret;
>  	}
>  	case VFIO_DEVICE_RESET:
>  	{
> @@ -303,6 +367,9 @@ static int vfio_fsl_mc_init_device(struct vfio_fsl_mc_device *vdev)
>  	struct fsl_mc_device *mc_dev = vdev->mc_dev;
>  	int ret = 0;
>  
> +	/* innherit the msi domain from parent */
> +	dev_set_msi_domain(&mc_dev->dev, dev_get_msi_domain(mc_dev->dev.parent));
> +
>  	/* Non-dprc devices share mc_io from parent */
>  	if (!is_fsl_mc_bus_dprc(mc_dev)) {
>  		struct fsl_mc_device *mc_cont = to_fsl_mc_device(mc_dev->dev.parent);
> diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c b/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
> new file mode 100644
> index 000000000000..058aa97aa54a
> --- /dev/null
> +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
> @@ -0,0 +1,63 @@
> +// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
> +/*
> + * Copyright 2013-2016 Freescale Semiconductor Inc.
> + * Copyright 2019 NXP
> + */
> +
> +#include <linux/vfio.h>
> +#include <linux/slab.h>
> +#include <linux/types.h>
> +#include <linux/eventfd.h>
> +#include <linux/msi.h>
> +
> +#include "linux/fsl/mc.h"
> +#include "vfio_fsl_mc_private.h"
> +
> +static int vfio_fsl_mc_irq_mask(struct vfio_fsl_mc_device *vdev,
> +				unsigned int index, unsigned int start,
> +				unsigned int count, u32 flags,
> +				void *data)
> +{
> +	return -EINVAL;
> +}
> +
> +static int vfio_fsl_mc_irq_unmask(struct vfio_fsl_mc_device *vdev,
> +				unsigned int index, unsigned int start,
> +				unsigned int count, u32 flags,
> +				void *data)
> +{
> +	return -EINVAL;
> +}
> +
> +static int vfio_fsl_mc_set_irq_trigger(struct vfio_fsl_mc_device *vdev,
> +				       unsigned int index, unsigned int start,
> +				       unsigned int count, u32 flags,
> +				       void *data)
> +{
> +	return -EINVAL;
> +}
> +
> +int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,
> +			       u32 flags, unsigned int index,
> +			       unsigned int start, unsigned int count,
> +			       void *data)
> +{
> +	int ret = -ENOTTY;
> +
> +	switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
> +	case VFIO_IRQ_SET_ACTION_MASK:
> +		ret = vfio_fsl_mc_irq_mask(vdev, index, start, count,
> +					   flags, data);
> +		break;
> +	case VFIO_IRQ_SET_ACTION_UNMASK:
> +		ret = vfio_fsl_mc_irq_unmask(vdev, index, start, count,
> +					     flags, data);
> +		break;
> +	case VFIO_IRQ_SET_ACTION_TRIGGER:
> +		ret = vfio_fsl_mc_set_irq_trigger(vdev, index, start,
> +						  count, flags, data);
> +		break;
> +	}
> +
> +	return ret;
> +}
> diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
> index d072cccd93e0..0c7506e43880 100644
> --- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
> +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
> @@ -37,4 +37,9 @@ struct vfio_fsl_mc_device {
>  	struct vfio_fsl_mc_reflck   *reflck;
>  };
>  
> +extern int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,
> +			       u32 flags, unsigned int index,
> +			       unsigned int start, unsigned int count,
> +			       void *data);
> +
>  #endif /* VFIO_PCI_PRIVATE_H */
>